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View Full Version : Question about fish oil and DHA(Docosahexaenoic acid):


Zelenius
16th December 2008, 10:02 PM
I often supplement with fish oil to get extra DHA(Docosahexaenoic acid) in my diet. Many studies show that DHA and omega 3s, which are essential for human health, are especially beneficial for the brain. Ever since I started supplementing, I've experienced fewer headaches, I could concentrate better and I don't get depressed as often(maybe it has improved my sex drive, but that is debatable :blush: ). Avoiding fried foods or over-heated polyunsaturated oils helps as well. I eat a mostly vegetarian diet, and I'd like to avoid fish as much as possible due to the toxins that accumulate in them. I realize flaxseeds contain omega 3s as well, but not DHA - only EPA and other fats. In many people, the EPA can be converted to DHA in the liver, but some people are very limited in their ability to do this, and some can't do it at all(this ability may be due to genetics).

I'm trying to figure out which is better: DHA derived from fish, or DHA derived from algae. The DHA in fish ultimately comes from the smaller fish they eat and the DHA-containing algae near the bottom of the oceanic food chain. According to Dr Weil - "If you do take supplements, fish oil is a better source of DHA than algae because it contains these fatty acids in the form that the body requires. " - http://www.drweil.com/drw/u/id/QAA244314 . So according to him, and some other sources, fish oil is superior for humans, compared to algae DHA, but only for adults. On the other hand, algae DHA seems to be superior for infants. Dr Weil doesn't go into any detail on this. I quote him on this since I can't find any other source that states this so explicitly.

While Dr Weil may occasionally dabble in woo and nonsense, most of his health advice seems accurate and helpful enough. He does unfortunately recommend a few homeopathic remedies :boggled:, but he isn't a practicing homeopath and homeopathy isn't central to his practice. So my question is: Is the DHA in fish really superior for adult human consumption, compared to the DHA in algae? If so, why? What is the difference between the DHA in fish and the DHA in algae, besides concentration? And the omega 3s and DHA in omega 3 eggs - are they the exact same thing as the omega 3s in fish? Or is the DHA in fish and algae the same exact thing, but there are other fatty acids or co-factors in fish that help utilize the DHA? If you are a nutritionist, chemist, or biologist(I know you guys are out there :D ) you may go into as much scientific detail as you want, since I studied biology and chemistry for many years. I tried discussing this with my doctor, but he claims he doesn't know. I'm not suffering from any disease or on any meds, but if I become deficient in omega 3s, especially DHA, I believe my risk of returning to an earlier state of woo belief is significantly increased. Thank you :)

Please note : I am not trying to push DHA supplementation or any supplementation. I'm not promoting or endorsing Dr Weil's site, views, books or supplements. In fact, I never buy anything from him.

Happy whatever-it-is-that-you-celebrate or don't celebrate.

http://www.mrc.ac.uk/Newspublications/News/MRC001720

http://www.nutraingredients.com/Research/Fish-for-brain-health-supported-by-trio-of-studies

Kuko 4000
17th December 2008, 01:01 AM
I'm sorry I can't help, I just hope you get some informative answers, this whole omega-thing is confusing to a layperson like me.

Evilgiraffe
17th December 2008, 01:49 AM
From a purely chemistry point of view, DHA is DHA no matter where it is derived from. The only caveat to place on this is, it must be pure DHA. It is entirely possible there may be different trace impurities in each source of DHA that affect its bioavailability (http://en.wikipedia.org/wiki/Bioavailability).

We've now reached the limit of my understanding of how the body utilizes compounds as I'm only a simple inorganic chemist. Someone else will have to take up the explanations from here.

Zelenius
17th December 2008, 07:37 PM
From a purely chemistry point of view, DHA is DHA no matter where it is derived from. The only caveat to place on this is, it must be pure DHA. It is entirely possible there may be different trace impurities in each source of DHA that affect its bioavailability (http://en.wikipedia.org/wiki/Bioavailability).

We've now reached the limit of my understanding of how the body utilizes compounds as I'm only a simple inorganic chemist. Someone else will have to take up the explanations from here.

I've been thinking along similar lines, but can't get enough details on all those co-factors that may be effecting bioavailability. That's a good start though.